A lot of the extant harnesses are built around interaction, which adds a bunch of complexity.

Eg an agent that only runs off a webhook trigger doesn’t have a use for all the UI stuff Pi does (and you may not want the local state like Pi does by default).

I’m still sort of with you, I’d generally do ACP to an open source agent. You do get much finer grained control if you use one of these agent SDKs (there’s a bajillion of these as well).